U.S. patent number 10,837,351 [Application Number 15/738,173] was granted by the patent office on 2020-11-17 for method for regulating an internal combustion engine.
This patent grant is currently assigned to INNIO Jenbacher GmbH & Co OG. The grantee listed for this patent is INNIO Jenbacher GmbH & Co OG. Invention is credited to Ettore Musu, Nikolaus Spyra, Josef Thalhauser.
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United States Patent |
10,837,351 |
Thalhauser , et al. |
November 17, 2020 |
Method for regulating an internal combustion engine
Abstract
A method for controlling an internal combustion engine whereby,
in a piston-cylinder unit provided with a prechamber, the quantity
of propellant gas supplied to the prechamber is adjusted to
regulate the operating characteristics of an inlet and/or outlet
valve of the piston-cylinder unit.
Inventors: |
Thalhauser; Josef (Nuborf,
DE), Spyra; Nikolaus (Innsbruck, DE), Musu;
Ettore (Garching b. Munchen, DE) |
Applicant: |
Name |
City |
State |
Country |
Type |
INNIO Jenbacher GmbH & Co OG |
Jenbach |
N/A |
AT |
|
|
Assignee: |
INNIO Jenbacher GmbH & Co
OG (Jenbach, AT)
|
Family
ID: |
56463974 |
Appl.
No.: |
15/738,173 |
Filed: |
June 24, 2016 |
PCT
Filed: |
June 24, 2016 |
PCT No.: |
PCT/AT2016/050232 |
371(c)(1),(2),(4) Date: |
May 08, 2018 |
PCT
Pub. No.: |
WO2017/000011 |
PCT
Pub. Date: |
January 05, 2017 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20180252150 A1 |
Sep 6, 2018 |
|
Foreign Application Priority Data
|
|
|
|
|
Jun 30, 2015 [AT] |
|
|
416/2015 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F02D
19/0673 (20130101); F02D 41/0027 (20130101); F02D
19/02 (20130101); F02D 41/0002 (20130101); F02B
19/1052 (20130101); F02D 13/02 (20130101); F02D
19/00 (20130101); F02B 19/1085 (20130101); F02D
19/0647 (20130101); F02B 43/12 (20130101); F02D
13/0203 (20130101); F02D 19/027 (20130101); F02D
2200/0406 (20130101); F02D 2041/001 (20130101); Y02T
10/40 (20130101); F02D 19/0678 (20130101); Y02T
10/12 (20130101); F02D 41/0007 (20130101); Y02T
10/30 (20130101) |
Current International
Class: |
F02B
19/10 (20060101); F02B 43/12 (20060101); F02D
13/02 (20060101); F02D 41/00 (20060101); F02D
19/06 (20060101); F02D 19/02 (20060101); F02D
19/00 (20060101) |
References Cited
[Referenced By]
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Other References
Office Action issued in connection with corresponding AT
Application No. A 416/2015 dated Jun. 17, 2016. cited by applicant
.
International Search Report and Written Opinion issued in
connection with corresponding PCT Application No. PCT/AT2016/050232
dated Oct. 14, 2016. cited by applicant .
International Preliminary Report on Patentabilty issued in
connection with corresponding PCT Application No. PCT/AT2016/050232
dated Jan. 2, 2018. cited by applicant .
Chinese Office Action for CN Application No. 201680039040.4 dated
Apr. 16, 2020; 13 pgs. cited by applicant.
|
Primary Examiner: Zaleskas; John M
Attorney, Agent or Firm: Fletcher Yoder, P.C.
Claims
The invention claimed is:
1. A method for controlling an internal combustion engine
comprising: providing a piston-cylinder unit with a main combustion
chamber and a prechamber; adjusting a quantity of a first
propellant gas supplied to the prechamber to vary a first energy in
the prechamber; adjusting, via a variable valve train, operating
characteristics of an inlet valve and/or an outlet valve to cause
adjusting of a quantity of a second propellant gas in the main
combustion chamber to vary a second energy in the main combustion
chamber, wherein adjusting the quantity of the second propellant
gas comprises decreasing or increasing the quantity of the second
propellant gas in the main combustion chamber; and controlling a
ratio between the first energy in the prechamber and the second
energy in the main combustion chamber, based on a target ratio of
the first energy to the second energy, wherein controlling the
ratio comprises: compensating for the decreasing of the quantity of
the second propellant gas in the main combustion chamber caused by
the variable valve train, by decreasing the quantity of the first
propellant gas supplied to the prechamber based on the target
ratio; and compensating for the increasing of the quantity of the
second propellant gas in the main combustion chamber caused by the
variable valve train, by increasing the quantity of the first
propellant gas supplied to the prechamber based on the target
ratio.
2. The method according to claim 1, wherein controlling the ratio
between the first energy in the prechamber and the second energy in
the main combustion chamber, comprises substantially maintaining
the ratio at the target ratio.
3. The method according to claim 1, wherein controlling the ratio
between the first energy in the prechamber and the second energy in
the main combustion chamber, comprises reducing the first energy
relative to the second energy to reduce the ratio based on the
target ratio.
4. The method according to claim 1, wherein adjusting the quantity
of the first propellant gas supplied to the prechamber includes
adjusting a charge-air pressure of the internal combustion
engine.
5. The method according to claim 1, wherein adjusting the quantity
of the first propellant gas supplied to the prechamber comprises
adjusting the quantity via an adjustment of an active prechamber
gas valve by setting an opening duration of the active prechamber
gas valve.
6. The method according to claim 1, wherein adjusting the quantity
of the first propellant gas supplied to the prechamber comprises
adjusting the quantity via an adjustment of an active aperture by
setting an opening degree of the active aperture.
7. The method according to claim 1, wherein adjusting the quantity
of the first propellant gas supplied to the prechamber comprises
adjusting the quantity via an adjustment of an actively
influenceable pressure regulator by setting a pressure applied to a
passive prechamber gas valve by the actively influenceable pressure
regulator.
8. An internal combustion engine, comprising: a piston-cylinder
unit comprising a main combustion chamber, an inlet valve, an
outlet valve, and a prechamber; a gas supply configured to adjust a
quantity of a first propellant gas supplied to the prechamber to
vary a first energy in the prechamber; a variable valve train
configured to adjust operating characteristics of the inlet valve
and/or the outlet valve to cause an adjustment of a quantity of a
second propellant gas in the main combustion chamber to vary a
second energy in the main combustion chamber, wherein the
adjustment of the quantity of the second propellant gas comprises
an increase or a decrease in the quantity of the second propellant
gas in the main combustion chamber; and a controller configured to
control a ratio between the first energy in the prechamber and the
second energy in the main combustion chamber, based on a target
ratio of the first energy to the second energy, wherein the
controller is configured to control the ratio by: compensating for
the decrease in the quantity of the second propellant gas in the
main combustion chamber caused by the variable valve train, by
decreasing the quantity of the first propellant gas supplied to the
prechamber based on the target ratio; and compensating for the
increase in the quantity of the second propellant gas in the main
combustion chamber caused by the variable valve train, by
increasing the quantity of the first propellant gas supplied to the
prechamber based on the target ratio.
9. The internal combustion engine of claim 8, wherein the
controller is configured to control the ratio to substantially
maintain the ratio at the target ratio.
10. The internal combustion engine of claim 8, wherein the
controller is configured to control the ratio to be reduced by
reducing the first energy relative to the second energy based on
the target ratio.
11. The internal combustion engine of claim 8, wherein the gas
supply comprises a passive prechamber gas valve.
12. The internal combustion engine of claim 8, wherein the gas
supply comprises an active prechamber gas valve, an active aperture
upstream of a passive prechamber gas valve, or an actively
influenceable pressure regulator.
13. A system, comprising: a controller configured to control a
ratio between a first energy of a first propellant gas in a
prechamber and a second energy of a second propellant gas in a main
combustion chamber of a piston-cylinder assembly, based on a target
ratio of the first energy to the second energy, wherein controlling
the ratio comprises: compensating for a decrease of the second
energy of the second propellant gas in the main combustion chamber
caused by a variable valve train, by decreasing the first energy of
the first propellant gas in the prechamber based on the target
ratio; and compensating for an increase of the second energy of the
second propellant gas in the main combustion chamber caused by the
variable valve train, by increasing the first energy of the first
propellant gas in the prechamber based on the target ratio.
14. The system of claim 13, wherein the controller is configured to
control the ratio to substantially maintain the ratio at the target
ratio.
15. The system of claim 13, wherein the controller is configured to
control the first energy in the prechamber by controlling a
quantity of the first propellant gas supplied to the prechamber,
wherein the controller is configured to control the second energy
in the main combustion chamber by controlling operating
characteristics of the inlet valve and/or the outlet valve of the
piston-cylinder assembly by the variable valve train to cause an
adjustment of a quantity of the second propellant gas in the main
combustion chamber.
16. The system of claim 13, wherein the controller is configured to
control the ratio based on the target ratio, by controlling the
quantity of the first propellant gas supplied to the prechamber via
one of: an adjustment of an active prechamber gas valve; an
adjustment of an actively influenceable pressure regulator; or an
adjustment of an active aperture upstream of a passive prechamber
gas valve.
17. The system of claim 13, wherein the controller is configured to
control the ratio to be reduced by reducing the first energy
relative to the second energy based on the target ratio.
18. The system of claim 13, wherein the controller is configured to
control the ratio based on the target ratio, by at least: measuring
a pressure associated with the second propellant gas; detecting a
position of the variable valve train; determining a volumetric
efficiency based on the position of the variable valve train; and
calculating a parameter to adjust the first propellant gas in the
prechamber based on the pressure and the volumetric efficiency.
19. The system of claim 13, comprising the piston-cylinder
assembly, a gas supply configured to supply the first propellant
gas to the prechamber, the variable valve train, or a combination
thereof.
20. The system of claim 13, comprising an internal combustion
engine having the controller.
Description
TECHNOLOGY FIELD
This invention relates to a method for regulating an internal
combustion engine. The invention also relates to an internal
combustion engine with the features of the preamble of claim 8.
BACKGROUND
DE 10 2012 021 778 A1 describes a method in which inequalities
between different piston-cylinder units of an internal combustion
engine are detected by cylinder pressure sensors and compensated
for by adjusting the quantities of propellant gas introduced into
the respective prechambers. If a cylinder of a piston-cylinder unit
has too low a volumetric efficiency, the quantity of propellant gas
supplied to the corresponding prechamber is increased
("overblowing" of the prechambers). It is therefore a measure to
compensate for differences in volumetric efficiency between
different piston-cylinder units. The prechamber is used to support
the combustion in the main combustion chamber of the corresponding
piston-cylinder unit. An adjustment of the operating
characteristics of an inlet and/or outlet valve of the
piston-cylinder unit is not provided according to this method. The
method requires cylinder pressure sensors or comparable sensors to
detect a cylinder-specific or cylinder bank-specific volumetric
efficiency.
It is known that an adjustment can be made to the operating
characteristics of an inlet and/or outlet valve of the
piston-cylinder unit via a variable valve train for the
piston-cylinder unit.
In principle, such variable valve trains could also be used in
generic internal combustion engines which have prechambers.
However, this is not yet known from the prior art.
A problem in the use of variable valve trains in internal
combustion engines with prechambers is that a variable valve train
affects the metering of the prechamber gas.
As a result, the ratio between the energy supplied to the main
combustion chamber and that of the prechamber changes, resulting in
suboptimal combustion in the piston-cylinder unit without
accompanying measures. The consequences are unfavorable efficiency,
increased pollutant emissions and possibly increased thermal loads
on the piston-cylinder unit.
BRIEF DESCRIPTION
The object of an embodiment of the invention is to provide a
generic method and a generic internal combustion engine in which
the above-described problems do not occur.
According to an embodiment of the invention, it is thus provided
that the quantity of propellant gas supplied to the prechamber is
adapted to an adjustment of the operating characteristics of an
inlet and/or outlet valve of the piston-cylinder unit.
It can be provided that, when adjusting the operating
characteristics such that the filling of the piston-cylinder unit
is reduced, the quantity of propellant gas supplied to the
prechamber is reduced. In this way, the ratio of the energy
supplied to the main combustion chamber and the energy supplied to
the prechamber can be kept constant.
For the reverse case, it can be provided that, when adjusting the
operating characteristics such that the filling of the
piston-cylinder unit is increased, the quantity of propellant gas
supplied to the prechamber is increased. In this way, the ratio of
the energy supplied to the main combustion chamber and the energy
supplied to the prechamber can be kept constant.
An embodiment of the invention makes it possible, regardless of the
selected operating characteristics of the inlet valves, to maintain
a ratio of the quantity of energy supplied via the prechamber gas
valve to the quantity of energy supplied to the piston-cylinder
unit via the inlet valves at least substantially constant, such
that approx. 1% of the quantity of energy is supplied via the
prechamber gas valve and approx. 99% of the quantity of energy is
supplied via the inlet valves.
This ensures that a mixture of charge originating from the
piston-cylinder unit and propellant gas supplied via the prechamber
gas valve with a desired ratio of air to propellant gas (lambda
value) always forms in the prechamber. This is important, on the
one hand, for emissions control, and on the other hand, to achieve
safe combustion with high efficiency in the piston-cylinder
unit.
This measure is performed such that the mixture in the prechamber
has a lambda value of approximately 1 or 1.1 at the ignition time,
whereby a lambda value of 1 corresponds to a stoichiometric ratio
and a lambda value greater than 1 to a surplus of air.
It may be provided to adapt the ratio of the quantities of energy
supplied to the main combustion chamber and the prechamber to
changed operating characteristics of an inlet and/or outlet valve,
e.g. valve control times, such that at "sharp" valve control times
(valve control times with a low degree of filling of the
piston-cylinder units), the energy fraction of the prechamber is
slightly reduced in favor of the main combustion chamber (e.g. to
less than 1%, e.g. to 0.7%, so as to remain in the above numerical
example). Operating characteristics with low degree of filling of
the piston-cylinder units cause a cooler charge of the
piston-cylinder units. While maintaining the emission
specifications, e.g. NOx, this allows operating with a richer
mixture, which in turn requires a lower ignition pulse from the
prechamber. Thus, it is possible in this case to further reduce the
energy supplied to the prechamber and to lean down the
prechamber.
An embodiment of the invention does not require feedback from the
combustion and is therefore a pure feedforward-controlled control
concept. A complex sensor system, e.g. cylinder pressure sensors,
is not required.
In this disclosure, "propellant gas" means both pure propellant gas
and a mixture of propellant gas and air. In other words, the
prechamber can be flushed with pure propellant gas or with a
mixture.
If an adjustment of the operating characteristics of the inlet
valves is performed at a constant target power, such that the
filling of the piston-cylinder unit is reduced, then a power
control circuit of the internal combustion engine attempts to
increase the filling of the piston-cylinder unit by increasing the
charge-air pressure until the same quantity of energy is again
supplied. The pressure prevailing before the prechamber gas valve
usually follows the charge-air pressure or is tracked to the
charge-air pressure. The quantity of propellant gas supplied to the
prechamber by the prechamber gas valve depends on the pressure
progression upstream of the prechamber gas valve--which tracks the
charge-air pressure--and on the cylinder pressure progression of
the associated piston-cylinder unit.
Since the former increases as described and the latter decreases if
necessary due to the reduced temperature of the charge in the
piston-cylinder unit, in the case of a change in the operating
characteristics such that the filling of the piston-cylinder unit
is reduced, the prechamber would be supplied with too large a
quantity of propellant gas.
A control device intervenes and adapts, e.g. via the pressure
prevailing upstream of the prechamber gas valve, the quantity of
propellant gas supplied to the prechamber such that the quantity is
reduced. The same applies mutatis mutandis in the case of an
increase in the filling of the piston-cylinder unit.
An adjustment of the operating characteristics can e.g. be such
that, by means of a variable valve train, the opening duration of
the corresponding valve and/or the opening or closing time of the
corresponding valve and/or the valve lift curve (in a fully
variable valve train) are changed. Simple variable valve trains can
be designed according to the prior art such that two discrete valve
lift curves for the valve can be activated selectively by two
different camshaft profiles.
One possibility of influencing the quantity of propellant gas
supplied via the prechamber gas valve is via an active prechamber
gas valve. An active prechamber gas valve, in contrast to a passive
valve which is activated only by a differential pressure, allows an
adjustment of the opening duration regardless of the pressure
applied to the prechamber gas valve.
An alternative possibility is to use an active aperture arranged
upstream of a passive prechamber gas valve. An active aperture has
an adjustable free cross-sectional area (setting of an opening
degree). The quantity of propellant gas supplied to the prechamber
can thus be varied with unchanged differential pressure between the
charge-air pressure and the prechamber gas supply pressure upstream
of the active aperture.
Alternatively or in addition to these two measures, the pressure
applied before the prechamber gas valve pressure can of course be
changed by means of an actively influenceable pressure regulator to
keep the differential pressure constant via the prechamber gas
valve, whereby the desired adjustment of the prechamber gas
quantity is achieved.
If, at constant charge-air pressure, e.g. the pressure in the main
combustion chamber increases due to a change in the operating
characteristics of the inlet valves towards a higher filling of the
main combustion chamber, then the pressure applied to the
prechamber gas valve must be increased accordingly to adjust the
differential pressure via the prechamber gas valve, such that the
ratio of the quantity of energy supplied via the prechamber gas
valve and the quantities of energy supplied through the inlet
valves remains constant. In other words, the changed volumetric
efficiency is taken into account here.
An even more accurate adjustment of the quantity of propellant gas
supplied to the prechamber can be achieved by additionally taking
account of the charge-air pressure such that, at a higher
charge-air pressure, the difference between the pressure upstream
of the prechamber gas valve and the pressure in the main combustion
chamber is not kept constant, but rather the difference is
increased by increasing the pressure upstream of the prechamber gas
valve. The purpose of this measure is to keep the ratio of the
energy supplied via the prechamber gas valve and the energy in the
main combustion chamber constant.
The volumetric efficiency and the density of the mixture (and thus
the mass in the cylinder) are also influenced by a changed mixture
temperature. It can therefore be provided to use the
above-described measure to compensate for a changed mixture
temperature.
When using an active prechamber gas valve as described above, an
opening time of the prechamber gas valve can be increased or
decreased, and an adjustment of the pressure prevailing upstream of
the prechamber gas valve is not necessarily required. However, a
higher charge-air pressure can of course also take into account
here with an appropriate opening time of the prechamber gas
valve.
The control device described here can be designed as a control
circuit of a regulating device of the internal combustion
engine.
More particularly, the internal combustion engine has a plurality
of piston-cylinder units, each being assigned its own prechambers,
whereby the control device proceeds in relation to each pair of
piston-cylinder units and prechambers according to one of the
embodiments described above.
To change the operating characteristics of at least one inlet valve
and/or outlet valve, the internal combustion engine has a variable
valve train (or VVT for short).
More particularly, the internal combustion engine is designed as a
stationary gas engine, in particular coupled or able to be coupled
to a generator for generating electricity.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is discussed with reference to the figures. The
figures show the following:
FIG. 1 shows a schematic representation of an internal combustion
engine
FIG. 2 a control diagram according to an exemplary embodiment of
the invention
FIG. 3 a diagram of the gas pressure applied to the prechamber gas
valve
DETAILED DESCRIPTION
FIG. 1 shows an internal combustion engine 1 with a plurality of
piston-cylinder units 3 (only one of which is shown in the
example). The piston-cylinder unit 3 is supplied with propellant
gas via inlet valves 4 (only one of which is shown). Exhaust gases
are discharged via outlet valves 5 (only one of which is shown).
Furthermore, a prechamber 2 is provided, which communicates via
overflow openings with a main combustion chamber 9 of the
piston-cylinder unit. The prechamber 2 is supplied with propellant
gas (either pure propellant gas or a mixture) via a prechamber gas
valve 7 which is designed here to be active.
In this exemplary embodiment, the operating characteristics of the
inlet valves 4 can be varied via a variable valve train 8. Not
shown is a fundamentally also (alternatively or additionally)
possible variation of the operating characteristics of the outlet
valves 5. The variable valve train 8 has a signal connection to a
control device 6 of the internal combustion engine 1 and is
controlled by the latter. The prechamber gas valve 7 that is also
active in this case has a signal connection to the control device 6
and is controlled by the latter.
In the prechamber gas supply 10, a pressure regulator 11 is
arranged, which has a signal connection to the control device 6 and
is controlled by the latter. This creates the possibility of
varying the pressure applied to the prechamber gas valve 7.
Propellant gas is supplied to the prechamber 2 from a propellant
gas source for the prechamber 12 via the prechamber gas supply 10,
the pressure regulator 11 and the prechamber gas valve 7.
Propellant gas is supplied to the main combustion chamber 9 from a
propellant gas source for the main combustion chamber 13, a
compressor 14, a mixture cooler 15, a throttle 16, an inlet duct 17
and the inlet valves 4.
The quantity of propellant gas supplied to the main combustion
chamber 9 can be changed via the variable valve train 8. The
quantity of propellant gas supplied to the prechamber 2 can be
adjusted via the prechamber gas valve 7 and/or the pressure
regulator 11 and/or the variable aperture 18.
FIG. 2 shows a control diagram according to a first exemplary
embodiment of the invention, in which, in a first step, the
charge-air pressure p2' prevailing in the inlet duct 17 and applied
to the inlet valve 4 is measured. From the operating
characteristics of the variable valve train 8 (in the diagram:
"Detection of the VVT position"), a volumetric efficiency is
determined by the control device 6. From the charge-air pressure
p2' and the volumetric efficiency, the pressure is calculated which
is required for the metering of the corresponding quantity of
propellant gas for the prechamber 2.
FIG. 3 shows a diagram of the pressure in the main combustion
chamber 9 (cylinder pressure) in the inlet stroke for two different
operating characteristics IVC1 and IVC2 (inlet valve closing) of an
inlet valve 4 plotted against the crank angle.
Also shown are two different pressure levels pVKG1 and pVKG2 of the
pressure applied in the prechamber gas supply 10 upstream of the
prechamber gas valve 7. The level of this pressure applied in the
prechamber gas supply 10 upstream of the prechamber gas valve 7 can
be changed by operating the pressure regulator 11.
The significant factor for the actual quantity of propellant gas
supplied to the prechamber 2 is the differential pressure
prevailing over the prechamber gas valve 7 between the cylinder
pressure and the pressure (pVKG1 or pVKG2) in the prechamber gas
supply 10 upstream of the prechamber gas valve 7.
Frequently, prechamber gas valves 7 are designed as passive valves
(also called check valves), which open at a certain positive
differential pressure and thus allow propellant gas to enter the
prechamber 2. "Positive" differential pressure means that the
pressure upstream of the prechamber gas valve 7 is greater than in
the prechamber 2 and in the main combustion chamber 9. A common
value (as chosen for this example) of a differential pressure
required to open a passive prechamber gas valve is 50 mbar.
If an inlet valve is moved to earlier closing in the inlet phase
(i.e. the inlet valve 4 closes at a larger crank angle before the
bottom dead center in the representation of IVC1 to IVC2), the
cylinder pressure decreases starting from the charge-air pressure
p2' in the main combustion chamber 9 (progression at IVC2) than in
the case of a later closing of the inlet valve (progression at
IVC1). This normally results in the fact that
The period in which the differential pressure upstream of the
prechamber gas valve 7 and prechamber 2 is greater than or equal to
the differential pressure required to operate the prechamber gas
valve 7 is extended compared to a later closing of the inlet valve.
As a result, more propellant gas enters the prechamber 2.
According to an embodiment of the invention, the changed quantity
of propellant gas supplied to the prechamber 2 due to the changed
operating characteristics of an inlet or outlet valve can now be
compensated for. In this exemplary embodiment, the compensation is
performed by lowering the pressure level pVKG1 to pVKG2 in the
prechamber gas supply 10 upstream of the prechamber gas valve 7 by
operating the pressure regulator 11.
The hatched area A1 corresponds to the quantity of prechamber gas
in the pressure progression at IVC1 and the pressure level pVKG1.
The hatched area A2 corresponds to the quantity of prechamber gas
in the pressure progression at IVC2 and the pressure level pVKG2.
By means of an embodiment of the invention, the quantity A2 can be
equalized with the quantity A1.
Due to the reduced pressure level, the ratio of the energy supplied
via the prechamber gas valve 7 and the energy supplied via the
inlet valves 4 is kept constant or even reduced, if desired. If the
pressure level pVKG1 were maintained in the operating
characteristic IVC2, this would result in an excessively high
quantity of prechamber gas.
Alternatively or additionally, it can be provided that the pressure
level upstream of the prechamber gas valve 7 is adjusted by an
aperture 18. In this case, the quantity of propellant gas supplied
to the prechamber 2 can be varied with unchanged differential
pressure between the outlet of the pressure regulator 11 and the
prechamber 2. This requires an active aperture 18. This has a
signal connection to the control device 6.
In the presence of an active (i.e. controllable) prechamber gas
valve 7, the ratio of the energy supplied via the prechamber gas
valve 7 and the energy supplied via the inlet valves 4 can be kept
constant by changing the opening duration of the prechamber gas
valve 7.
* * * * *